Source/DebuggerBackEnd.m

   1 /*
   2  * MacGDBp
   3  * Copyright (c) 2007 - 2011, Blue Static <http://www.bluestatic.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify it under the terms of the GNU
   6  * General Public License as published by the Free Software Foundation; either version 2 of the
   7  * License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
  10  * even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with this program; if not,
  14  * write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
  15  */
  16
  17 #import "DebuggerBackEnd.h"
  18
  19 #import "AppDelegate.h"
  20 #import "NSXMLElementAdditions.h"
  21
  22 // GDBpConnection (Private) ////////////////////////////////////////////////////
  23
  24 @interface DebuggerBackEnd ()
  25 @property (readwrite, copy) NSString* status;
  26
  27 - (void)recordCallback:(SEL)callback forTransaction:(NSNumber*)txn;
  28
  29 - (void)updateStatus:(NSXMLDocument*)response;
  30 - (void)debuggerStep:(NSXMLDocument*)response;
  31 - (void)rebuildStack:(NSXMLDocument*)response;
  32 - (void)getStackFrame:(NSXMLDocument*)response;
  33 - (void)setSource:(NSXMLDocument*)response;
  34 - (void)contextsReceived:(NSXMLDocument*)response;
  35 - (void)variablesReceived:(NSXMLDocument*)response;
  36 - (void)propertiesReceived:(NSXMLDocument*)response;
  37
  38 @end
  39
  40 // GDBpConnection //////////////////////////////////////////////////////////////
  41
  42 @implementation DebuggerBackEnd
  43
  44 @synthesize status;
  45 @synthesize attached = attached_;
  46 @synthesize delegate;
  47
  48 /**
  49  * Creates a new DebuggerBackEnd and initializes the socket from the given connection
  50  * paramters.
  51  */
  52 - (id)initWithPort:(NSUInteger)aPort
  53 {
  54   if (self = [super init])
  55   {
  56     stackFrames_ = [[NSMutableDictionary alloc] init];
  57     callbackContext_ = [NSMutableDictionary new];
  58     callTable_ = [NSMutableDictionary new];
  59
  60     [[BreakpointManager sharedManager] setConnection:self];
  61     connection_ = [[NetworkConnection alloc] initWithPort:aPort];
  62     connection_.delegate = self;
  63     [connection_ connect];
  64
  65     attached_ = [[NSUserDefaults standardUserDefaults] boolForKey:@"DebuggerAttached"];
  66   }
  67   return self;
  68 }
  69
  70 /**
  71  * Deallocates the object
  72  */
  73 - (void)dealloc
  74 {
  75   [connection_ close];
  76   [stackFrames_ release];
  77   [callTable_ release];
  78   [callbackContext_ release];
  79   [super dealloc];
  80 }
  81
  82
  83 // Getters /////////////////////////////////////////////////////////////////////
  84 #pragma mark Getters
  85
  86 /**
  87  * Gets the port number
  88  */
  89 - (NSUInteger)port
  90 {
  91   return [connection_ port];
  92 }
  93
  94 /**
  95  * Returns whether or not we have an active connection
  96  */
  97 - (BOOL)isConnected
  98 {
  99   return [connection_ connected] && active_;
 100 }
 101
 102 // Commands ////////////////////////////////////////////////////////////////////
 103 #pragma mark Commands
 104
 105 /**
 106  * Tells the debugger to continue running the script. Returns the current stack frame.
 107  */
 108 - (void)run
 109 {
 110   NSNumber* tx = [connection_ sendCommandWithFormat:@"run"];
 111   [self recordCallback:@selector(debuggerStep:) forTransaction:tx];
 112 }
 113
 114 /**
 115  * Tells the debugger to step into the current command.
 116  */
 117 - (void)stepIn
 118 {
 119   NSNumber* tx = [connection_ sendCommandWithFormat:@"step_into"];
 120   [self recordCallback:@selector(debuggerStep:) forTransaction:tx];
 121 }
 122
 123 /**
 124  * Tells the debugger to step out of the current context
 125  */
 126 - (void)stepOut
 127 {
 128   NSNumber* tx = [connection_ sendCommandWithFormat:@"step_out"];
 129   [self recordCallback:@selector(debuggerStep:) forTransaction:tx];
 130 }
 131
 132 /**
 133  * Tells the debugger to step over the current function
 134  */
 135 - (void)stepOver
 136 {
 137   NSNumber* tx = [connection_ sendCommandWithFormat:@"step_over"];
 138   [self recordCallback:@selector(debuggerStep:) forTransaction:tx];
 139 }
 140
 141 /**
 142  * Ends the current debugging session.
 143  */
 144 - (void)detach
 145 {
 146   [connection_ sendCommandWithFormat:@"detach"];
 147   active_ = NO;
 148   self.status = @"Stopped";
 149   if ([delegate respondsToSelector:@selector(debuggerDisconnected)])
 150     [delegate debuggerDisconnected];
 151 }
 152
 153 /**
 154  * Tells the debugger engine to get a specifc property. This also takes in the NSXMLElement
 155  * that requested it so that the child can be attached.
 156  */
 157 - (NSInteger)getChildrenOfProperty:(VariableNode*)property atDepth:(NSInteger)depth;
 158 {
 159   NSNumber* tx = [connection_ sendCommandWithFormat:@"property_get -d %d -n %@", depth, [property fullName]];
 160   [self recordCallback:@selector(propertiesReceived:) forTransaction:tx];
 161   return [tx intValue];
 162 }
 163
 164 - (void)loadStackFrame:(StackFrame*)frame
 165 {
 166   if (frame.loaded)
 167     return;
 168
 169   NSNumber* routingNumber = [NSNumber numberWithInt:frame.routingID];
 170   NSNumber* transaction = nil;
 171
 172   // Get the source code of the file. Escape % in URL chars.
 173   if ([frame.filename length]) {
 174     NSString* escapedFilename = [frame.filename stringByReplacingOccurrencesOfString:@"%" withString:@"%%"];
 175     transaction = [connection_ sendCommandWithFormat:@"source -f %@", escapedFilename];
 176     [self recordCallback:@selector(setSource:) forTransaction:transaction];
 177     [callbackContext_ setObject:routingNumber forKey:transaction];
 178   }
 179
 180   // Get the names of all the contexts.
 181   transaction = [connection_ sendCommandWithFormat:@"context_names -d %d", frame.index];
 182   [self recordCallback:@selector(contextsReceived:) forTransaction:transaction];
 183   [callbackContext_ setObject:routingNumber forKey:transaction];
 184
 185   // This frame will be fully loaded.
 186   frame.loaded = YES;
 187 }
 188
 189 // Breakpoint Management ///////////////////////////////////////////////////////
 190 #pragma mark Breakpoints
 191
 192 /**
 193  * Send an add breakpoint command
 194  */
 195 - (void)addBreakpoint:(Breakpoint*)bp
 196 {
 197   if (![connection_ connected])
 198     return;
 199
 200   NSString* file = [connection_ escapedURIPath:[bp transformedPath]];
 201   NSNumber* tx = [connection_ sendCommandWithFormat:@"breakpoint_set -t line -f %@ -n %i", file, [bp line]];
 202   [self recordCallback:@selector(breakpointReceived:) forTransaction:tx];
 203   [callbackContext_ setObject:bp forKey:tx];
 204 }
 205
 206 /**
 207  * Removes a breakpoint
 208  */
 209 - (void)removeBreakpoint:(Breakpoint*)bp
 210 {
 211   if (![connection_ connected])
 212     return;
 213
 214   [connection_ sendCommandWithFormat:@"breakpoint_remove -d %i", [bp debuggerId]];
 215 }
 216
 217 // Specific Response Handlers //////////////////////////////////////////////////
 218 #pragma mark Response Handlers
 219
 220 - (void)errorEncountered:(NSString*)error
 221 {
 222   [delegate errorEncountered:error];
 223 }
 224
 225 /**
 226  * Initial packet received. We've started a brand-new connection to the engine.
 227  */
 228 - (void)handleInitialResponse:(NSXMLDocument*)response
 229 {
 230   if (!self.attached) {
 231     [connection_ sendCommandWithFormat:@"detach"];
 232     return;
 233   }
 234
 235   active_ = YES;
 236
 237   // Register any breakpoints that exist offline.
 238   for (Breakpoint* bp in [[BreakpointManager sharedManager] breakpoints])
 239     [self addBreakpoint:bp];
 240
 241   // Load the debugger to make it look active.
 242   [delegate debuggerConnected];
 243
 244   // TODO: update the status.
 245 }
 246
 247 - (void)handleResponse:(NSXMLDocument*)response
 248 {
 249   NSInteger transactionID = [connection_ transactionIDFromResponse:response];
 250   NSNumber* key = [NSNumber numberWithInt:transactionID];
 251   NSString* callbackStr = [callTable_ objectForKey:key];
 252   if (callbackStr)
 253   {
 254     SEL callback = NSSelectorFromString(callbackStr);
 255     [self performSelector:callback withObject:response];
 256   }
 257   [callTable_ removeObjectForKey:key];
 258 }
 259
 260 /**
 261  * Receiver for status updates. This just freshens up the UI.
 262  */
 263 - (void)updateStatus:(NSXMLDocument*)response
 264 {
 265   self.status = [[[[response rootElement] attributeForName:@"status"] stringValue] capitalizedString];
 266   active_ = YES;
 267   if (!status || [status isEqualToString:@"Stopped"]) {
 268     [delegate debuggerDisconnected];
 269     active_ = NO;
 270   } else if ([status isEqualToString:@"Stopping"]) {
 271     [connection_ sendCommandWithFormat:@"stop"];
 272     active_ = NO;
 273   }
 274 }
 275
 276 /**
 277  * Step in/out/over and run all take this path. We first get the status of the
 278  * debugger and then request fresh stack information.
 279  */
 280 - (void)debuggerStep:(NSXMLDocument*)response
 281 {
 282   [self updateStatus:response];
 283   if (![self isConnected])
 284     return;
 285
 286   // If this is the run command, tell the delegate that a bunch of updates
 287   // are coming. Also remove all existing stack routes and request a new stack.
 288   if ([delegate respondsToSelector:@selector(clobberStack)])
 289     [delegate clobberStack];
 290   [stackFrames_ removeAllObjects];
 291   NSNumber* tx = [connection_ sendCommandWithFormat:@"stack_depth"];
 292   [self recordCallback:@selector(rebuildStack:) forTransaction:tx];
 293   stackFirstTransactionID_ = [tx intValue];
 294 }
 295
 296 /**
 297  * We ask for the stack_depth and now we clobber the stack and start rebuilding
 298  * it.
 299  */
 300 - (void)rebuildStack:(NSXMLDocument*)response
 301 {
 302   NSInteger depth = [[[[response rootElement] attributeForName:@"depth"] stringValue] intValue];
 303
 304   if (stackFirstTransactionID_ == [connection_ transactionIDFromResponse:response])
 305     stackDepth_ = depth;
 306
 307   // We now need to alloc a bunch of stack frames and get the basic information
 308   // for them.
 309   for (NSInteger i = 0; i < depth; i++)
 310   {
 311     // Use the transaction ID to create a routing path.
 312     NSNumber* routingID = [connection_ sendCommandWithFormat:@"stack_get -d %d", i];
 313     [self recordCallback:@selector(getStackFrame:) forTransaction:routingID];
 314     [stackFrames_ setObject:[[StackFrame new] autorelease] forKey:routingID];
 315   }
 316 }
 317
 318 /**
 319  * The initial rebuild of the stack frame. We now have enough to initialize
 320  * a StackFrame object.
 321  */
 322 - (void)getStackFrame:(NSXMLDocument*)response
 323 {
 324   // Get the routing information.
 325   NSInteger routingID = [connection_ transactionIDFromResponse:response];
 326   if (routingID < stackFirstTransactionID_)
 327     return;
 328   NSNumber* routingNumber = [NSNumber numberWithInt:routingID];
 329
 330   // Make sure we initialized this frame in our last |-rebuildStack:|.
 331   StackFrame* frame = [stackFrames_ objectForKey:routingNumber];
 332   if (!frame)
 333     return;
 334
 335   NSXMLElement* xmlframe = [[[response rootElement] children] objectAtIndex:0];
 336
 337   // Initialize the stack frame.
 338   frame.index = [[[xmlframe attributeForName:@"level"] stringValue] intValue];
 339   frame.filename = [[xmlframe attributeForName:@"filename"] stringValue];
 340   frame.lineNumber = [[[xmlframe attributeForName:@"lineno"] stringValue] intValue];
 341   frame.function = [[xmlframe attributeForName:@"where"] stringValue];
 342   frame.routingID = routingID;
 343
 344   // Only get the complete frame for the first level. The other frames will get
 345   // information loaded lazily when the user clicks on one.
 346   if (frame.index == 0) {
 347     [self loadStackFrame:frame];
 348   }
 349
 350   if ([delegate respondsToSelector:@selector(newStackFrame:)])
 351     [delegate newStackFrame:frame];
 352 }
 353
 354 /**
 355  * Callback for setting the source of a file while rebuilding a specific stack
 356  * frame.
 357  */
 358 - (void)setSource:(NSXMLDocument*)response
 359 {
 360   NSNumber* transaction = [NSNumber numberWithInt:[connection_ transactionIDFromResponse:response]];
 361   if ([transaction intValue] < stackFirstTransactionID_)
 362     return;
 363   NSNumber* routingNumber = [callbackContext_ objectForKey:transaction];
 364   if (!routingNumber)
 365     return;
 366
 367   [callbackContext_ removeObjectForKey:transaction];
 368   StackFrame* frame = [stackFrames_ objectForKey:routingNumber];
 369   if (!frame)
 370     return;
 371
 372   frame.source = [[response rootElement] base64DecodedValue];
 373
 374   if ([delegate respondsToSelector:@selector(sourceUpdated:)])
 375     [delegate sourceUpdated:frame];
 376 }
 377
 378 /**
 379  * Enumerates all the contexts of a given stack frame. We then in turn get the
 380  * contents of each one of these contexts.
 381  */
 382 - (void)contextsReceived:(NSXMLDocument*)response
 383 {
 384   // Get the stack frame's routing ID and use it again.
 385   NSNumber* receivedTransaction = [NSNumber numberWithInt:[connection_ transactionIDFromResponse:response]];
 386   if ([receivedTransaction intValue] < stackFirstTransactionID_)
 387     return;
 388   NSNumber* routingID = [callbackContext_ objectForKey:receivedTransaction];
 389   if (!routingID)
 390     return;
 391
 392   // Get the stack frame by the |routingID|.
 393   StackFrame* frame = [stackFrames_ objectForKey:routingID];
 394
 395   NSXMLElement* contextNames = [response rootElement];
 396   for (NSXMLElement* context in [contextNames children])
 397   {
 398     NSInteger cid = [[[context attributeForName:@"id"] stringValue] intValue];
 399
 400     // Fetch each context's variables.
 401     NSNumber* tx = [connection_ sendCommandWithFormat:@"context_get -d %d -c %d", frame.index, cid];
 402     [self recordCallback:@selector(variablesReceived:) forTransaction:tx];
 403     [callbackContext_ setObject:routingID forKey:tx];
 404   }
 405 }
 406
 407 /**
 408  * Receives the variables from the context and attaches them to the stack frame.
 409  */
 410 - (void)variablesReceived:(NSXMLDocument*)response
 411 {
 412   // Get the stack frame's routing ID and use it again.
 413   NSInteger transaction = [connection_ transactionIDFromResponse:response];
 414   if (transaction < stackFirstTransactionID_)
 415     return;
 416   NSNumber* receivedTransaction = [NSNumber numberWithInt:transaction];
 417   NSNumber* routingID = [callbackContext_ objectForKey:receivedTransaction];
 418   if (!routingID)
 419     return;
 420
 421   // Get the stack frame by the |routingID|.
 422   StackFrame* frame = [stackFrames_ objectForKey:routingID];
 423
 424   NSMutableArray* variables = [NSMutableArray array];
 425
 426   // Merge the frame's existing variables.
 427   if (frame.variables)
 428     [variables addObjectsFromArray:frame.variables];
 429
 430   // Add these new variables.
 431   NSArray* addVariables = [[response rootElement] children];
 432   if (addVariables) {
 433     for (NSXMLElement* elm in addVariables) {
 434       VariableNode* node = [[VariableNode alloc] initWithXMLNode:elm];
 435       [variables addObject:[node autorelease]];
 436     }
 437   }
 438
 439   frame.variables = variables;
 440 }
 441
 442 /**
 443  * Callback from a |-getProperty:| request.
 444  */
 445 - (void)propertiesReceived:(NSXMLDocument*)response
 446 {
 447   NSInteger transaction = [connection_ transactionIDFromResponse:response];
 448
 449   /*
 450    <response>
 451      <property> <!-- this is the one we requested -->
 452        <property ... /> <!-- these are what we want -->
 453      </property>
 454    </repsonse>
 455    */
 456
 457   // Detach all the children so we can insert them into another document.
 458   NSXMLElement* parent = (NSXMLElement*)[[response rootElement] childAtIndex:0];
 459   NSArray* children = [parent children];
 460   [parent setChildren:nil];
 461
 462   [delegate receivedProperties:children forTransaction:transaction];
 463 }
 464
 465 /**
 466  * Callback for setting a breakpoint.
 467  */
 468 - (void)breakpointReceived:(NSXMLDocument*)response
 469 {
 470   NSNumber* transaction = [NSNumber numberWithInt:[connection_ transactionIDFromResponse:response]];
 471   Breakpoint* bp = [callbackContext_ objectForKey:transaction];
 472   if (!bp)
 473     return;
 474
 475   [callbackContext_ removeObjectForKey:callbackContext_];
 476   [bp setDebuggerId:[[[[response rootElement] attributeForName:@"id"] stringValue] intValue]];
 477 }
 478
 479 // Private /////////////////////////////////////////////////////////////////////
 480
 481 - (void)recordCallback:(SEL)callback forTransaction:(NSNumber*)txn
 482 {
 483   [callTable_ setObject:NSStringFromSelector(callback) forKey:txn];
 484 }
 485
 486 @end